Technical and medical endoscopes are delicate optical instruments that are introduced into technical and human cavities to inspect the interiors thereof. Such endoscopes can be rigid endoscopes containing a lens system, flexible endoscopes containing a flexible image guiding bundle or video endoscopes. Typically, endoscopes contain an outer tube and an inner tube. The space between the outer tube and the inner tube is filled with illumination fibers which guide externally created light inside of the cavities. Within the inner tube of rigid endoscopes there is provided an optical system which relays an image of the cavity from the distal tip of the endoscope back to the proximal end of the endoscope. This relayed image can be observed at the proximal end by the operator's eye or captured by a video camera. Rigid endoscopes are inserted along an insertion tube which cannot freely move in the body cavity. Thus, to look at a direction sideward to the insertion direction rigid endoscopes often have a deflecting prism at the distal tip of the optical system. For flexible endoscopes, the cavity image is relayed by a fiber image bundle to the ocular at the proximal end of the endoscope. Video endoscopes have a chip built into the distal tip of the endoscope that delivers the cavity image in electronic form directly to an external video controller.
Because of the extreme physical dimensions of endoscopes, endoscopes are often stressed during cleaning, sterilization and usage. These stresses can bend the endoscopes or break, chip or dislocate the glass lenses and deflection prisms. Further, the illumination fibers can break, and debris can accumulate on the ends of the fiber illumination bundle or on the windows enclosing the optical system. Also, fluid can enter into the optical system of the instruments during cleaning or sterilization. Accordingly, endoscopes can be damaged or their performance degraded to an extent where the safe usage of the instruments is no longer warranted.
When endoscopes are damaged, they must be separated from the inventory and properly cleaned or sent out to a service company for internal cleaning or repair. If the damage is not detected prior to the planned surgery the medical procedure can be delayed, cancelled or the outcome of the procedure can be compromised.
In the patent literature various test equipment for endoscopes is described. U.S. Pat. Nos. 6,203,492 and 6,673,011 describe testing devices that hold and protect endoscopes when the pupil of the endoscopes are scanned for damage and debris. These testing devices are easy to use but do not give a clear determination if the equipment is ready for use or not. The testing devices described in U.S. Pat. Nos. 4,613,232; 5,966,210 and 6,498,642 use time consuming procedures to collect data and require technical knowledge and skills to operate. Further, the data have then to be checked against the manufacturer's specifications and tolerances. U.S. Pat. Nos. 6,069,691 and 7,022,065 describe testing devices for endoscopes which are automated or computer controlled. These devices are less complicated to operate, but they are expensive and delicate.